Axle Flange Gaskets - Dana 70 and Like
 

Full Floating Axle Flange Gaskets

For Dana 70 (and possibly several others as the axle flange can't be any larger than the center of a 8-on-6-1/2 wheel regardless of how big the rest of it may be):
Fel-Pro 55328 --- Victor Reinz 326212

QUESTION = Do you use a flange gasket or do you omit the gasket and only use a sealant; and, what are your observations and experiences on this ?

For years and years, on countless floating axles, I only ever used NO GASKET and apply a bead of silicone; I never ever had a leak nor any other problems.

Then, ten or so years ago, on my F-350, for whatever reason and I have no idea just what possessed me to do this, I got a brand-new pair of those hard plastic flange gaskets.

Gaskets are supposed to prevent leaks, right ?

At first, figuring the gaskets would do their job of preventing leaks and wanting to get away from the mess of using silicone, I tried just the gaskets alone, under proper 90-ft-lbs torque.

They leaked like a sieve, slinging droplets all around the inside of my simulators.

So, like an idiot, instead of ditching the gaskets and going back to my tried and true silicone only method; what did I do --- I applied a bead of silicone to BOTH sides of the gasket --- it never dawned on me that this was taking twice the silicone that I used to use.

The last few times, instead of silicone, I have been using and much prefer Mr. Gasket Form-a-Gasket #2 Non-hardening Sealer.

And then, last night, after I struggled to squish out enough Mr. Gasket to make it the rest of the way around the second side of the gasket, slid the axle home, and torqued the bolts, I made an executive decision = from this day forward, no more axle flange gaskets for me.

As I ponder upon this, I am wondering if possibly (and probably) the axle flange gaskets might not have caused another issue I was having.

In all the years and all the many many floating axles, I had NEVER had an axle bolt to loosen, let alone back out and disappear completely.

Whether the gaskets had anything to do with it or not, a few years ago, after I started using the gaskets, I came home from a trip and noticed specks of lube spattered inside my wheels.

Then, I noticed one axle bolt completely gone.

I checked that side and found I could easily turn every bolt at least half-a-turn.

I went around to the other side; and, although no bolts were missing, every bolt head had an eighth between it and the flange; well, between the lock-washer behind the bolt and the flange.

I replaced the missing bolt and torqued all of them and a few weeks later found them loose again.

After that, I keep the socket, extension, and long breaker-bar handy and check them regularly while I have nightmares of an axle sliding out and going off in some deep kudzu holler never to be seen again and stranding me thouwzands of miles from home.

I can't help but wonder if that plastic gasket might not be shrinking in thickness and allowing enough slack for the bolts to begin loosening.

The right axle flange bolts don't use a washer. They are a flanged bolt spicer 45720. If your axle flange holes have worn egg-shaped from being loose, you may have to replace the axle shaft.

I should say, that I run lockers on most of my diffs, so that's got to be harder on things.

The diff I have had most trouble with bolts backing out is the 10.25" ford. I believe it's because the o-ring seal precludes the need for a gasket. The lack of gasket means metal-on-metal at the flange instead of a cured silicone 'snubber'.

Maybe not, but every Ford Dana I have worked on has normal split lock-washers and normal bolts.

I will look at the Dodges, Chevrolets with Danas, and big goosenecks around here with Dana axles and see what they have.

know the Dana 70 under the son's 90 Dodge W-250 has split conical seat washers and normal bolts factory original; that is the best set-up but you have to whack the axle with something to get them to pop loose --- and hope you never lose one of those conical washers as I don't know where you would ever find another except maybe have a machinist whittle some out.

I think dodge was the last to give up the studs/nuts and conical washers around '90-91. I have them like this, or the flanged bolts. My two D70 E350 diffs use flanged bolts too - late '90's vintage.

Sitting on over a dozen fullfloaters now and none have factory split-style lock-washers.